FUNGUS OF TUENIP DISEASE. 



Oidium Balsamii Mont. 



A.B. Shows the thickness of the lamina of a turnip leaf with 

 the Oidium growing upon both the upper and lower surfaces. 



C. One of the stomato, or organs of transpiration,' seen in 

 section on the under side of leaf choked over with the spawn of 

 the fungus. 



D.D. Cellular tissue of the leaf. 



E. Spiral vessels belonging to a veinlet of ditto, all enlarged 

 360 diameters. 



F. A germinating spore on the epidermis of leaf (0, stomate 

 or organ of transpiration). 



G. Young spore on the tip of thread which has emerged from 

 the germinating spore, enlarged 480 diameters. 



